TACLOBAN, Philippines — Increasingly desperate survivors of Typhoon Haiyan mobbed the shattered airport here Tuesday, begging for food, water, or a flight to escape the chaotic aftermath of the storm, which flattened this city of 220,000 five days earlier and ravaged vast swaths of the country’s midsection.

Even as an enormous global aid effort gathered momentum and relief supplies began trickling in to the airport here and elsewhere, officials did not have a full grasp of the magnitude of the devastation and could provide no guidance on when basic emergency needs could be met.

While President Benigno S. Aquino III suggested in a CNN interview that estimates of 10,000 or more dead may turn out to be high, international relief officials said they were still assuming the worst and expressed worry that bottlenecks and delays could prevent them from reaching millions of victims for days.

Officials in Manila found themselves on the defensive, asserting that they were doing the best they could despite a storm that Valerie Amos, the top UN relief coordinator, who flew to the capital Tuesday to help take charge of efforts, called the “most deadly and destructive” to hit the Philippines. She pleaded for more than $300 million in emergency aid.

“There has been a lot of commentary that relief is not moving as fast as it should be,” said Praveen Agrawal, the World Food Program’s Philippines representative and country director. “The reality on the ground is there is such a level of devastation.”

The travails reached new heights Tuesday in Tacloban, a formerly thriving city in the east-central Philippines that appeared to get the full force of the typhoon. Wearing face masks or pulling their shirts up over their noses to suppress the smell of bodies rotting on the streets, a procession of survivors 3 miles long walked toward the airport, where relief supplies had begun to arrive.

They witnessed the despair of survivors like Erroll de la Cruz, 34, who squatted next to the pavement to scrawl the names of his wife, Michelle, and her 7-year-old son, Matthew, on a piece of plywood. Then he walked across the crowded road and laid the plywood between their corpses, in the hope that their lives would be remembered, and perhaps their bodies someday traced.

The people of Tacloban, on Leyte Island in the east-central Philippines, have been struggling largely on their own to deal with the devastation of Typhoon Haiyan.

Some residents were understanding of the delays in distributing food. Lamberto Patau, 31, a bus dispatcher, said more relief shipments had arrived than could be handed out. “There is food, but there is no one to distribute it, because they were all victims,” he said.

The devastation apparent during an 8-mile drive into the city center made the extent of the challenge clear. Mounds of debris up to 15 feet high towered next to the main road. Concrete pillars and other hazards had fallen into the traffic lanes, forcing drivers, motorcyclists, and pedestrians to dodge and weave.

Police officers were operating a series of simple checkpoints, built of little more than scraps of wood, to try to restrain unruly behavior. An 8 p.m. curfew has been imposed.

Jennifer Cicco, the administrator of the Leyte Island chapter of the Philippines Red Cross, said the conservative estimate from provincial officials was that in addition to the deaths in Tacloban, a city of 220,000, about 10,000 people had died in surrounding Leyte province, home to 1.3 million. Almost all of those lived on the coast, where many fishing villages were unprepared for the fury of the storm.

Some officials have estimated that up to 10,000 people died in Tacloban alone, although the official death toll for the entire country was 1,798 as of Tuesday evening, according to the National Disaster Risk Reduction and Management Council. But many of the hardest-hit areas had not yet been reached.

The airport still had no radar or other effective air traffic control system; it was contacting the relief planes via radio once they came within 9 to 12 miles of the city, and asking them to take turns using the runway. Only small planes with limited capacity, mostly propeller planes, could use the airport, because of the air traffic control problem and the lack of portable staircases for reaching the doorways of larger jets.

US officials in Washington said later Tuesday that the Philippine authorities had asked the Air Force to help manage traffic at the airport and send radar and electronic equipment for a temporary tower, which will allow navigation at night and in poor weather.

In the city, conditions were even worse than on the road. So many rotting bodies lay uncollected in the streets that senior Filipino military officers complained of severe nausea from the stench. Water and food were scarce, and looters picked through the mangled remains of retail stores in the hope of finding anything of value that previous looters might have missed.

Mayor Alfred S. Romualdez of Tacloban said in a brief interview that he was aware of difficulties, but described them as affecting nearby villages more than his own city. “These communities are very difficult to access,” he said.

Romualdez said he had personally lost everything, including his house.

But he suggested that reports of damage to Tacloban might have been exaggerated, saying that only a couple of hundred deaths had been confirmed by the authorities.